Process of producing low boiling point oils or motor fuel from hydrocarbon oils by the employment of metallic halides



g- R. A. HALLORAN ET AL 1,872,446

PROCESS OF PRODUCING LOW BOILING POINT OILS OR MOTOR FUEL FROMHYDROCARBON OILS BY THE EMPLOYMENT OF METALLIC HALIDES Filed March 16.1927 COPIIFHSER CONDENSER IlzvuLeann-rn I Jam 11A W. W

(lbtozwugo gwwntou Patented Aug. 16, 1932 UNITED STATES PATENT OFFICERALPH A. HALLORAN, OF BERKELEY, MARVIN L. CHAPPELL, 01' LOS ANGELES, AND

JAMES HAROLD OSMER, OF EL SEGUNDO, CALIFORNIA, ASSIGNORS T STANDARD OILCOMPANY OF CALIFORNIA, OF SAN FRANCISCO, camonlvrmn CORPORATION OFDELAWARE PROCESS OF PRODUCING LOW BOILING POINT OILS OB MOTOR FUEL PROMHYDRO- CARBON OILS BY THE EMPLOYMENT O]? METALLIC HALIDES Applicationfiled March 16, 1927. Serial No. 175,83IL

' This invention relates to the treatment of hydrocarbon oils withmetallic halides for the purpose of producing low boiling point oils ormotor fuel.

The process of the present invention is intended to provide a method bywhich a maximum amount of motor fuel of low sulfur content can beproduced from hydrocarbon oil with a minimum consumption of metallichalide. In accordance with the process of the present invention,hydrocarbon oil such as crude petroleum oil free of water is firstdistilled to remove-therefrom the natural motor fuel ongljsoline contentwhile at the same time, meta 'c halide is introduced into the vaporsunder regulated conditions so that the metallic halide in this stage ofthe process acts only or substantially only to remove sulfur from thenatural gasoline content of the crude oil, and causes somepolymerization of highly unsaturated constituents. Said metallic halideand condensed oil of too high boiling point for use as motor fuel iscontinuously passed from the first distllling operation to a reactionzone wherein the metalp lic halide and high boiling point oil aremaintained at a reactmg temperature for the production of motor fuel ornaphtha through a metallic halide cracldng reaction.

- ,By the process of the present invention,

the metallic halide comes into contact with the natural gasoline contentof the hydrocarbon oil under conditions where it operates to purify thenatural gasoline content of the oil without substantially impairing itspower for converting other higher boiling fractions ofthe oil to motorfuel or naphtha. Moreover, the aluminum chloride reaction which formsmotor fuel from the higher boiling constituents of the petroleum oil isconducted upon a selected stock or fraction of the crude oil and bymeansof the same metallic halide employed in purifying the naturalgasoline content. Moreover,- use is made in the metallic halidetreatment of such selected fraction of the residual heat in saidfraction left from the primary or first distilling operation. Thus, bythe process of the present invention, not only is the metallic halidecaused to produce gasoline from higher boiling point oils but saidmetallic halide is caused to remove from the natural gasoline content ofthe oil the sulfur components and highly unsaturated constituents withthe result that the natural gasoline derived is freed of gum formingconstituents. This purification of the natural gasoline of the crude isalso effected without said metallic halide being expended in itsstrength through reaction to se arate all of the unsaturatedconstituents o the natural gasoline. Agreat portion of the unsaturatedconstituents of natural gasoline are not detrimental in. motor fuelandthis class of unsaturated constituents is not substantially reacted uponby the metallic halide under the conditions of the present process.

The process of the present invention may also be employed for thetreatment of distillates derived from a pressure distilling or crackingoperation, in which case the pressure naphtha may be separated from saidstock with a refluxing of the heavier oils and with the simultaneousremoval of sulfur comounds from the pressure naphtha without all of thestrength of the metallic halide being expended in this treatment.Moreover, the metallic halide-will react to polymerize from the pressurenaphtha only those highly unsaturated constituents which, ifleft in thenaphtha, will polymerize and produce gums or resins.

The present invention, together with various objects and advantagesthereof will best be understood from a description of a preferred formof process embodying the invention. For-this purpose, a preferredexample of the process is hereinafter described. The process isdescribed as it is carried out in the apparatus illustrated in theaccompanying drawing.

The drawing represents a diagrammatic view ofthe apparatus in elevationand main ly in vertical section.

Referring to the drawing, 2 indicates a still or vaporizing chamberwhich is connected by a vapor line'3 with the dephlegmator or refluxtower 4. The tower 4 is connected by a vapor line 5 with a condenser 6which discharges into a receiver 7 for receiving gasoline or motor fuel.Said receiver 7 is provided with a line 8 connected with a vacuum pump 9by means of which vacuum may be maintained upon the still 2, tower 4 andcondenser 6, if desired.

The still 2 is provided with suitable heating means, for example, beingmounted on a furnace 10 having a burner 11, and the still is alsopreferably provided with a residuum withdrawal line 12. The oiltobeprocessed enters the apparatus from a source, not shown, through 1111613, and passes through a heat exchanger 14 in the dephlegmator or refluxtower 1 and hence by line 15 into the vaporizing chamber or still 2.Preferably the oil to be treated enters the still 2 through thedistributor or spray producing device 16.

At the top of the dephlegmator or tower 4, there is preferably provideda metallic halide charger 17 by which metallic halide in either solid orliquid form may be introduced into the system. 18 indicates a lineconnected with the dephlegmator 4, preferably at a point spaced abovethe bottom of the dephlegmator for withdrawing c'ondensate and metallichalide. The line 18 is provided with a pump 19 by which the admixturemay be placed under increased pressure and forced into a dephlegmator20. The dephlegmator 20 is connected by a vapor line 21 with a reactionchamber 22. The dephlegmator 20 is also provided with a vapor line 23passing through a condenser 24 and hence to a receiver 25 for receivingnaphtha produced by metallic halide reaction upon the hydrocarbon oil.The dephlegmator 20 is also connected by a condensate line 26 with thereaction chamber 22.

The reaction chamber 22 may be of any construction adapted for agitatingor contacting metallic halide and hydrocarbon oil together at a reactiontemperature and is indicated as preferably mounted over a furnace 27having a burner 28 for supplying the heat for the reaction. The reactionchamber 22 is also indicated as provided with suitable agitating means29 and with a charger 3") by which additional metallic halide may beadded if desired and with a residual withdrawal line 31.

The preferred process, as carried out in the described apparatus, is asfollows: Any substantially water-free hydrocarbon oil may be employed,whether of petroleum, shale, or coal origin, but preferably ahydrocarbon oil is employed which contains some natural or alreadyformed motor fuel content along with heavier or higher boiling pointoils. For example, the process is particularly de-' signed for theprocessing of crude petroleum oil but is also of value in treatingdistillates derived from hydrocarbonoils by a thermal cracking process.The process will be first described with particular reference to thetreatment of crude petroleum oil or other oil in which the motor fuelcontent possesses only a comparatively small amount of unsaturatedconstituents. Said oil is passed through the heat exchanger 14 and henceinto the still or vaporizing chamber 2 where in it is heated to atemperature suflicient to vaporize the motor fuel content together withsome heavier or higher boiling point oils and the vapors passed throughline 3 into the dephlegmator 4. The temperature of the oil in vaporizingchamber 2 is, for example, maintained at between 450 to 550 F., and thedistillation may be facilitated by the maintenance of a reduced pressureor vacuum upon the distilling apparatus applied by vacuum pump 9. Thevacuum maintained is normally between 2 inches and 9 inches of mercuryabsolute pressure. In order to facilitate the evolution of the vapors instill 2, the crude oil from line 15 is preferably caused to enter thebody of oil in reaction chamber 2 in a plurality of jets. Said jets byagitating the oil within the still 2 facilitate the copious evolution ofvapors therefrom. Such conditions of temperature and pressure vaporizefrom the hydrocarbon oil the gasoline or motor fuel content, togetherwith the higher boiling point oils such, for example, as fall within theso-called kerosene cut range and some of the so-called gas oilfractions. Within the dephlegmator '4, the vapors are subjected tofractionization so that onl the gasoline or motor fuel fractions escapet rough vapor line 5 and are collected in the gasoline receiver 7. Theheavier fractions are condensed at different points in the dephlegmator4.

imultaneously with the passage of vapors through the dephlegmator 4,metallic halide is introduced into the top of the tower. The metallichalide to be employed is usually anhydrous aluminum chloride, althoughsimilar results may be obtained by other metallic halides such as ferricchloride. The metallic halide is introduced into the dephlegmator 4 forthe purpose of reacting with the sulfur compounds of the gasolinecontent of the oil and for the purpose of polymerizing or removing thosehighly unsaturated oils which would otherwise form gums in the gasolineproduced. At the same time, it is not desired to polymerize or removeall of the unsaturated constituents of the gasoline by the metallichalide. Accordingly the metallic halide in the reflux tower 4 is eithernot in troduced in sufficient quantities to react with all of theunsaturated constituents, or the metallic halide is contacted with theoils or vapors in dephlegmator 4 only in the upper or cooler portions ofsaid tower, or the metallic halide may be both introduced ininsufiicient quantities to polymerize all the unsaturated constituentsof the gasoline and be contacted with the gasoline vapors in only theupper or cooler portions of the dephlegmator. In this stage ofoperation, themetallic halide operates mainly upon such compounds asdiolefines and acetylenes without r substantial reaction upon thearomatic constituents.

Since it is not necessary to have a large amount of metallic halide inthe dephlegmator 4, preferably only a relatively small amount ofmetallic halide is introduced therein such, for example, as from .05 of1 per cent. to .2 or 1 per cent. by weight of metallic halide per gallonof vaporized oil, although it is understood that the greater quantitiesof metallic halide may be introduced, provided the reaction is suitablyconfined by withdrawing the metallic halide from the upper portions ofthe tower 4.

The operation of the process is preferably continuous and the metallichalide commingled with condensed oil in tower 4 is continuouslywithdrawn through line 18. The line 18 preferably communicates withdephlegmator 4 where the condensed oil in said dephlegmator is at atemperature below 450 F., and preferably at a point above the bottom ofthe dephlegmator 4 so that there is withdrawn with the metallic halidemainly only the kerosene fractions of the oil, the gas oil fractionsbeing permitted to return to m the still from the lower end of the towerthrough line 32. Another method of operating is possible, however. Thisconsists in removing all the metallic halide and reflux condensatethrough line 32.

The commingled condensed oils together with the metallic halide areplaced under increased pressure by pump 19 and continuously passedthrough dephlegmator 20 and line 26 into the reaction chamber 22,although, if desired, they may be run directly from dephlegmator 4 tochamber 22.

Within the reaction chamber 22, the metallic halide and hydrocarbon oilis heated up to a temperature suflicient to cause the metallic halide toreact upon the oil for the conversion of said oil to low boiling pointoil or naphtha. In case the quantity of metallic halide added to the oilin dephlegmator 4 is insuflicient for this purpose, additional metallichalide may be introduced into reaction chamber 22 from charger 30. Forexample, sufiicient additional metallic halide is introduced in reactionchamber 22 to bring the metallic halide in the reaction chamber up tofrom between 4 to 10 per cent. of the oil in reaction chamber 22.

, In reaction chamber 22, the reactionmay be continued with theproduction of a liquid metallic halide sludge which is continuouslywithdrawn from line 31 or the metallic halide may be reduced to a cokeand the alumina recovered -for conversion into aluminum chloride by wellknown processes. In eithercase, the produced naphtha is continuouslyvanorized and the vapors passed through the dephlegmator 20 and finallycollected in receiver 25. Preferably a pressure somewhat aboveatmospheric is maintained upon the admixture during this reaction such,for example, as a pressure of about 15 pounds per square inch gage. Thepreferred temperature of the admixture within the reaction chamber 22 isbetween 500 F. and 650 F.

By the process thus described, the metallic halide is adapted to purifythe gasoline content of the hydrocarbon oil to be treated withoutsubstantially impairing its powers to react upon the heavier boilingpoint oils for the conversion of the same to naphtha. Moreover, this isaccomplished without the metallic halide reacting upon the aromatic-constituents of the oil which have boiling points within the gasolinerange.

When the process of the present invention is employed for the treatment.of distillates derived by the thermal decomposition of hydrocarbon oils,due to the high percentage of unsaturated constituents having boilingpoints within the naphtha range, the vapors of such pressure distillatesare contacted in dephlegmator 4 only with a comparatively small amountof metallic halide or at a comparatively low temperature. The admixedcondensed oils and metallic halide from dephlegmator 4 are thenpreferably passed into reaction chamber 22 and the admixture maintainedat a temperature below 550 F. to polymerize the remaining oil to formhigh grade lubricating oil. It is understood, however, that at times,the reaction in chamber 22 even with such pressure distillates may becarried on for the production of naphtha. It is further understood thatthe process may be operated for the production of lubricating stock whenemploying other than cracked distillate.

It is understood that the naphthas derived from the present inventionmay be processed in any suitable manner for the removal of any hydrogenchloride gas or other usual or customary refining operations.

While the process herein described is well adapted to carry out theobjects of the present invention, it is understood that variousmodifications and changes and substitution of equivalents may be madewithout departing from the invention, and the invention includes allsuch modifications, changes, and substitution of equivalents as comewithin the scope of the appended claim.

We claim:

A process of treating hydrocarbon oil containing motor fuel fractionsand heavier fractions with metallic halide which motor fuel fractionscontain acetylenes, diolefines, and sulfur compounds, which comprisesdistilling said oil under a. reduced pressure less than atmospheric,fractionating the evolved vapors to separate the motor fuel fractions,contacting metallic halide with the vapors being fractionated to removetherefrom mainly acetylenes, diolefines and sulfur compounds before anydecomposing action of the metallic halide upon the heavier fractions,Withdrawing Vcommingled metallic halide and condensed oils from saidfractionating zone, and contacting the same at a temperature sufficientfor the metallic halide to decompose a part of said condensed oils toform lower boiling point oils. Signed at Los Angeles this 28th day 0February, 1927.

MARVIN L. CHAPPELL. Signed at San Francisco this 4th day of March, 1927.

RALPH A. HALLORAN. JAMES HAROLD OSMER.

